29 Nov Geological Resources Assistant
The purpose of this project will be to collect and analyze groundwater, vegetation stress, and newly collected pond water-quality samples to develop a conceptual model of the groundwater system of Jamestown Island. It is part of a larger research and monitoring project to determine the impact of sea-level rise on both the natural and cultural resources on the island. The applicant will be working in the field collecting samples under the direction and mentorship of USGS hydrologists who are directing this research. Work will include
1. Soil sampling across the island (and metadata documentation) (approx. 50 sample sites)
2. Collecting GPS-points of 8 ponds extents (maybe repeat through the growing season)
3. Downloading transducers and making measurements of pond stage
4. Creating plots of pond data and with well and tide data.
5. Working up vegetation survey data ( species tables, maps, charts) of habitats surrounding interior ponds and work with USGS mapping staff to analyze plant stress patterns.
6. Collect any fauna data of herps as they observe and compare the species with the 2005 and 2015 inventories completed in the park. Identifying amphibians such as frogs is an indicator of fresh or saline water environments which can become a vital sign for a changing habitat.
Basic methods include using Small diameter (3/8-inch) Henry push point samplers inserted by hand into the beds of open ponds and within forested wetlands. Henry samplers will be equipped with manometers to evaluate spatial patterns in hydraulic head gradients and the direction of flow between the ponds and underlying groundwater systems. Field parameters including pH, SC, and DO will be measured directly in ponds using multi-parameter water-quality meters and indirectly in groundwater through small syringes or peristaltic pumps used with Henry samplers. Bottles will be filled for stable isotopes and sent for analysis at the USGS Reston Stable Isotope lab to support conclusions from field observations and assess possible evaporative enrichment (i.e. deuterium excess) of bed sediment pore water in the case of recharging ponds.
Vegetation transects will be completed in and along the edges of the ponds leading 50-100 feet outward into the adjacent vegetation to capture species diversity, association to wet/dry habitat, and signs of stress based on marsh migration/surface water increase.